The invention will find an application in particular as a gas intake device, for admitting said gases to the cylinder head of a motor vehicle internal combustion engine.
A motor vehicle internal combustion engine comprises a plurality of combustion chambers each delimited by a piston, a cylinder, and a portion of a cylinder head. These combustion chambers receive a mixture of oxidant and of fuel which are supposed to be burnt in order to generate the work provided by the engine. The oxidant contains air, which may or may not be compressed, depending on whether or not the engine is fitted with a turbocharger. The air may moreover be mixed with exhaust gases; these are then referred to as recirculated exhaust gases. The gases admitted to the combustion chamber will hereinafter be referred to as feed gases.
It is known practice to increase the density of these feed gases by cooling them, for example by encouraging exchange of heat between the feed gases and a stream of air external to the vehicle, using an air/air heat exchanger.
It is also known practice to perform this cooling by exchange of heat between the feed gases and a liquid fluid circulating through a heat exchanger through which the feed gases pass. The effectiveness of such a solution is dependent on the use of all the frontal surface area of the heat exchanger core and on the quantity of feed gases being distributed across the entirety of this surface area.
Unfortunately, the space available in the vehicle compartment containing the internal combustion engine is limited. It is difficult to design airboxes or ducts capable of supplying the entire surface area of the heat exchanger uniformly, particularly when the stream of feed gas is parallel to the plane of the surface of the heat exchanger that receives this stream. Further, the inlet surface area of the airbox is generally markedly lower than the surface area of the exchanger receiving the stream of feed gas.
Adding a deflector in the duct improves the situation but the deflector leads to undesirable pressure drops. Moreover, this deflector is an additional component that has to be added to and fixed into an intake airbox admitting the feed gases, making that airbox more complicated to produce.
It is an object of the present invention to resolve the disadvantages described hereinabove chiefly by creating a feed gas inlet airbox cover, otherwise known as intake airbox, which delimits at least two ducts for channeling these gases in distinct zones of the frontal surface of the exchanger.